As is conventional, the hinge between the cutting blades of a manual cutting tool, as in the specific case of pruning shears, both those that are workable with one hand and those workable with two hands, is created by means of a bolt which traverses the two blades or counter-blades of the tool, with a retaining nut collaborating with that bolt and which prevents the said blades or counter-blades from coming loose or separating, furthermore defining the means of adjustment of the actual hinge.
Moreover, in order to prevent the bolt from rotating and becoming slack, it has flat faces or additional cotters since the adjustment is done by rotating the nut.
Other means or systems are also known in which the retention of the nut is done by means of using self-locking nuts or even by means of incorporating certain additional pieces or elements, which implies a greater complexity and, more importantly, a greater difficulty for the user when it comes to adjusting the tightness of the tool under consideration, making it necessary to use special tools or devices for being able to carry out the adjustment operations on the corresponding hinge, in the event of incorporating additional pieces or elements.